House mice and man need not have been the best of friends, but they accompanied the two-legged Homo sapiens on their colonising crusade.
Study co-author Eleanor Jones (affiliated with the Universities of York (Britain) and Uppsala (Sweden) said: "Human settlement history over the last 1,000 years is reflected in the genetic sequence of mouse mitochondrial DNA. We can match the pattern of human populations to that of the house mice."
Analysis of mouse mitochondrial DNA (which powers the cell) showed that they hitched a lift with the Vikings, in the early 10th century, into Iceland, either from Norway or the northern part of the British Isles, the journal BMC Evolutionary Biology reports.
However, while their descendants can still be found in Iceland, the early colonizers in Greenland have become extinct and their role has been filled by interloping Danish mice brought by a second wave of European human immigrants.
A team of researchers from Britain, the US, Iceland, Denmark and Sweden used techniques designed to characterize genetic similarity, and hence the relatedness of one population, or one individual, with another, to determine a mouse colonization timeline.
-Indo-Asian News Service st/rg/vm